Recent research has found that even preschoolers give more resources to others who have previously given resources to them. but the psychological bases of this reciprocity are unknown. In our study. a puppet distributed resources between herself and a child by taking some from a pile in front of the child or else by giving some from a pile in front of herself. https://www.roneverhart.com/Arjo-Sara-Stedy-Stand-Assist-Manual-Patient-Standing-Aid/